1. Field of the Invention
The invention relates to the automatic recording of radio programs, television programs and the like.
2. Description of the Prior Art
With the ready availability of high quality audio and video tape recorders, more and more consumers are recording their own libraries of television programs, films, music and the like. While such recording is desirable in that it provides each consumer with a collection of recorded programs tailored to his or her personal tastes, nevertheless two problems arise. First, a consumer generally likes to record only selected programs or portions of programs with commercials or other interruptions edited out. This generally requires that the consumer know in advance when a desired program will be transmitted, and that he or she be present at the time of the transmission, perched over the recording apparatus to edit out any undesired commercial breaks. Second, some programs are protected by the copyright laws, so can be legally recorded only with authorization from the copyright owner.
Attempts to solve the first problem have yielded devices for automatically switching a recorder on and off at the beginning and conclusion of a desired program. Such devices generally use one of two approaches. In the time-synchronized approach a device containing a clock can be set to turn the recording apparatus on and off at the scheduled start and end times of the desired program. In the program-triggered approach every transmitted program is accompanied by an identifying signal. An automatic switching device controlling the recorder is activated by this signal. The identification signal itself may consist merely of start and end codes transmitted at the beginning and end of the program, or it may be transmitted continuously throughout the program. To cause a desired program to be recorded in this type of device, the consumer enters a program code into a memory associated with the device, so that the device can recognize and respond to the transmitted program identification signal.
While both of these approaches provide suitable automatic actuation of a recorder, neither of these devices provides any protection for copyrighted programs. Indeed, for a program transmitted over the "free air wave," these devices facilitate copying, authorized or otherwise.
Some manner of protection for copyrighted works can be provided by subscription services. In these services programs are transmitted either over cable or, in a scrambled form, over the air. A subscriber receives either a cable hookup or a device for unscrambling the scrambled transmission. In this scheme the subscription fee can include the prorated royalty to be paid to the copyright owners whose material has been transmitted. Such a method has the obvious drawback that the subscriber pays a prorated royalty whether or not he or she records any programs. Furthermore, the scheme requires either a cable hookup, which is not uniformly available, or expensive and complicated apparatus for descrambling scrambled programs transmitted over the air.